The present invention generally relates to beverage dispensing containers and more specifically to a lid assembly for use with beverage dispensing containers.
A variety of beverage dispensing containers are available which include a body portion having a thermal barrier and a lid assembly which attaches to the body portion to prevent the escape of moisture, heat, and to prevent spilling should the container be tipped. An example of such a container and lid assembly can be found in U.S. Pat. No. 5,038,959 to Patel and in U.S. Pat. No. 4,739,898 to Brown. Both of the lid assemblies shown in Patel and Brown allow a brewed beverage to be dispensed into the container through an opening in the top of the lid assembly. Once the beverage is dispensed into the container, the lid assembly prevents the evaporative loss of moisture from the beverage. Additionally, both lid assemblies provide a degree of spill resistance when the container is tipped.
An important factor involved in lid assemblies used with such containers, in addition to and to be balanced with the factors presented above, is that the lid assembly must also allow the body of the container to "breathe" so that beverage may be easily dispensed from the container. Absence of a breathing vent generally results in the development of a vacuum in the container thereby hampering the dispensing of beverage from the container. An example of the vent passage can be found in Patel which provides a vent groove through the mouth of the container. The vent groove communicates with the threads of the lid and with free breathing holes formed through the lid. Threads between the lid and the container are formed with a dimensional deviation to provide an air passage space therebetween to facilitate venting. Additionally, free breathing vent holes formed through the lid allow air to vent freely through the lid.
While Patel provides venting to prevent the development of a vacuum in the container, such vents also facilitate dripping or leaking when the container is tipped. Additionally, the general free breathing nature of the vents in Patel allow unnecessary evaporation over extended periods of time. Evaporation is extremely detrimental to the coffee brewing arts such that the flavor and consistency of the brewed coffee dramatically changes upon evaporative loss of water from the mixture. As such, Patel does not sufficiently balance the compelling factors of venting, spill prevention and evaporation minimization.